Windows and some larger applications may load a hair faster. You'd have to use a stopwatch and count the hundredths of a second.
Some things will definately go a lot faster though, such as copying over a gigabit network with another computer that has as fast a HDD setup, or editing videos or huge photos.
Basically, what benefits the most from RAID 0 is anything that needs to read/write huge tracts of land^H^H^H er, I mean huge contiguous blocks of data. This means big files.